°C SI derived
Measures: Temperature — how hot or cold
Degree Celsius
The world's everyday temperature unit.
TemperatureHow it's defined
Exactly the kelvin scale shifted so 0 °C sits at 273.15 K — roughly where water freezes at sea level. Same step size as the kelvin; different zero.
T(K) = T(°C) + 273.15 — exacta step of 1 °C = a step of 1.8 °F — exact
Convert — honestly
°C equals
274.15 K
Kelvin · factor exact — the base unit itself
33.8 °F
Degree Fahrenheit · factor exact — exact by definition
Conversions run through the kelvin using the stated factors — no rounding beyond display precision, and every factor says whether it's exact or measured.
Where you meet it
- Temperaturii — its climate record is differences in this unit ↗ open temperaturii
- Nearly every weather forecast outside the US
Other ways to measure temperature
Source
This page is an authored summary of the authoritative definition — checkable one click away.
BIPM — The International System of Units (SI Brochure, 9th ed.)